Eklof, Paul C.; Fischer, Edward R. (1972), "The elementary theory of abelian groups", Annals of Pure and Applied Logic, 4 (2): 115–171, doi:10.1016/0003-4843(72)90013-7, MR0540003.
Eklof, Paul C.; Fischer, Edward R. (1972), "The elementary theory of abelian groups", Annals of Pure and Applied Logic, 4 (2): 115–171, doi:10.1016/0003-4843(72)90013-7, MR0540003.